This invention relates generally to hand operated fertilization tools, and more particularly to a fertilization tool which removes a column of soil and then facilitates deposit of a quantity of fertilizer into the hole.
The effective fertilization of plants, trees, and shrubs can best be accomplished by depositing granular fertilizers deep into the ground so that the fertilizer may readily reach deeply located roots that usually cannot be reached by conventional methods of fertilizing. Current methods of fertilizing, which include fertilizer spikes, injection of liquids into the soil, and application of either liquid or granular fertilizer to the surface or just slightly below the surface, are limited in their effectiveness because they either do not reach deep enough, or only provide for application of small amounts of fertilizer which does not facilitate continuous feeding over time.
The present invention provides for infusion of a substantial amount of fertilizer into the ground which, as it dissolves, provides for continuous feeding over an extended period of time. This invention is unique in that it provides a simple tool and method for deeply fertilizing trees, shrubs and plants. Other available methods for achieving deep fertilization require sophisticated, bulky, and costly apparatus that must be driven by powered equipment. These types of tools are generally impractical for the typical home gardener, arborist or gardening hobbiest.
Examination of the prior art reveals the following disclosures for depositing granular fertilizers into the ground:
U.S. Pat. No. 4,549,611 to Mills provides for cutting a shallow gutter at the surface of the soil into which fertilizer is then deposited;
U.S. Pat. No. 4,079,680 to Davis teaches a type of hoe that trenches and loosens the soil while fertilizer is injected to mix in with the loosened dirt behind the trenching tool. (This tool applies fertilizer to surface and sub-surface levels only);
U.S. Pat. No. 4,246,854 to Lempa,Jr. is directed to a fertilizer injection tool which is used to spade a shallow hole in the ground and then injects fertilizer in the ground and is capable of applying fertilizer at near-surface levels only;
U.S. Pat. No. 3,695,193 to Maier teaches a device that uses an electrically powered hole-boring arbor to produce a hole in the ground and then fill the hole with granular fertilizer which produces an end result similar to the present invention but the result is accomplished by an entirely different mechanism;
U.S. Pat. No. 2,170,598 to Sims discloses an apparatus to produce only a shallow hole in the ground with a built-in mechanism to allow filling the hole with fertilizer;
U.S. Pat. No. 2,325,939 to Buehler accomplishes much the same function a Sims but by a different mechanical means. Both Sims' and Buehler's disclosures concentrate on the automatic injection of fertilizer into the hole. The present invention concentrates on the depth of the hole and maintaining the native condition of the soil.
Other pertinent disclosures reviewed include:
U.S. Pat. No. 2,370,744 to Molinare PA1 U.S. Pat. No. 3,014,443 to Keyser PA1 U.S. Pat. No. 3,170,522 to Gregory PA1 U.S. Pat. No. 3,504,647 to Krarup PA1 U.S. Pat. No. 3,771,474 to Elston PA1 U.S. Pat. No. 3,815,526 to Christopherson
Each of these involves some variation of a tool to produce only a shallow hole in the ground and filling such hole with some granular substance be it fertilizer or rodent poison.
The present invention presents significant improvements over the above-mentioned devices in its ability to produce a deep hole while maintaining the native condition of the soil and permitting a slow, timely release of fertilization and access to deep roots that are not accessible by the above-mentioned disclosures.